Rotation sleeve for drill bits



W STEPHENS ROTATION SLEE E FOR palm. BITS 2 .n mm m n I s m u .W I 1 llllrl I'ILII t atented Aug. 14, 11923.

UNHTED STATE 'WILLIAM STEPHENS, 015 IRONWOOD, IdICHIGAN.

RQTATJION SLEEVE FOR DRILL BITS.

Application filed. March 29, 1922. Serial no. 547,811.

To all whom it may concern Be it known that T, WILLIAM STEPHENS, acitizen ofthe United States, residing at Ironwood, in the county ofGogebic and State of Michigan, have invented certain whereby rotarymovement is imparted to the drill bit as the drilling progresses. Oneobject of the invention is to provide a construction whereby theexternal retainer now very generally employed upon drills to maintainthe bit in alinement with the chuck may be dispensed with, and anotherobject of the invention is to provide a construction which will guidethe bit in its reciprocatory movements and will also prevent the bitbeing forced too far into the rotation sleeve. Other objects of theinvention will appear incidentally in the course of the followingdescription.

In the accompanying drawings, which illustrate my invention,-

Figure 1 is a view, partly in elevation and partly in vertical section,of a sleeve embodying my' improvements;

Fig.2 is a similar view showing the-drill bit in position within therotatlon sleeve and showing the sleeve partly in section upon the line22 of Fig. 1; o v Fig. 3 is a detail perspective View of the bit;

Fig. d is a transverse section on the line 44 of Fig. l with the bit inposition;

' Fig. 5 is a similar view with thebit removed.

The sleeve 1 is fitted in the lower end oi the drill casing in the usualmanner and is rotated intermittently by any of the means now generallyemployed for that purpose. The upper portion of the bore of the sleeve,indicated at 2, ma be smooth or may be provided with longitudinalgrooves or given any other desired confi ration according to thecharacteristics of t e drill in which it is to be fitted. It will beunderstood that the hammer head reciprocates in the upper portion of thebore of the sleeve and the sleeve should be correspondingly designed.

At its lower end, the bore of the sleeve is constructed with two rad1alnotches or grooves 3 which are arranged in allgn nt 'pass into saidgrooves.

and open at their inner sides into a central circular portion 4. Thecentral circular portion of the lower end of the bore merges at itsupper end into a recess or shallow chamber 5 formed in the wall of thebore and extending part way around the same, the chamber beingduplicated at diametrically opposite points and each chamber having onevertical side alined with and communicatin with a notch or oove 3. Eachcham or is further provi ed with an extenslon or notch 6 at its lowerend midway between the two notches or grooves 3 and open to the centralcircular portion 4 of the bore. The construction described provides lugs7 upon the wall of the lower portion of the sleeve at diametricallyopposite points, each lug being located at the side of a groove 3 andbeingiormed by one wall of said groove.

The bit comprises a shank 8 having a spiral blade 9 formed upon itsouter portion and provided at its upper or inner end with diametricallyopposite lugs 10, the portion of the shank between the lugs and theblade constituting a neck which, when the drill is in position withinthe sleeve, will fit within the circular portion 4: of the lower end ofthe sleeve. The blade is provided with abrupt shoulders 11 at its upperor inner end which form abutments adapted to engage against the lowerend of the sleeve, as shown clearly in Fig. 2, whereby to limit theinsertion of the drill into the sleeve.

When the drill is to be used, the upper end with the lugs 10 is insertedin the lower end of the sleeve with the lugs 10 engaging the grooves ornotches 3. The drill is then pushed upwardly or inwardly within thesleeve until the shoulders 11 abut the lower end of the sleeve, it beingunderstood that the said shoulders are somewhat wider than the groovesor notches 3 so that they cannot The insertion of the drill into thesleeve will bring the lugs 10 into positions in front of therespectively adjacent recesses or chambers 5, and the drill may then begiven a quarter turn until the lugs 10 abut the sides of therespectively adjacent lugs 7 above the seats or extensions 6. If thesleeve be then rotated, as indicated by the arrow in Fig. 4%, the drillwill also be rotated. When the drill has been given a quarter turn, asdescribed, the lugs 1,0 will, be i alinement with the extension or seats6 at the lower ends of the respective" chambers 5 and may seat in thesame so 'that rotation of the drill relative to the alinement of thedrill with the sleeve will be 7 maintained so that the usual retainersnow provided upon the outer or lower ends of drills will be unnecessary.

It will be understood that, if considered desirable, the usual bumperspring may be provided around the lower end of the rotation sleeve, butI have deemed illustration of this spring unnecessary inasmuch as it iswell-known in 'the art.

The construction of my sleeve is such that wear upon the bore of thesame is very materially reduced and, consequently, the life of thesleeve is prolonged and the force required to rotate the drill islessened.

Having thus described the invention, what is claimed as new is: v

1. In a drill, the combination of a rotation sleeve provided in itslower end with oppositely disposed longitudinally extending radialgrooves and a central circular portion connecting said grooves, thesleeve being furtherprovided between the grooves with recesses, eachcommunicating at one side with one of the grooves and having anextension at its lower end at its opposite side communicating With thecentral circular portion of the bore of the sleeve and closed to thegroove, and a drill bit provided at its upper end with diametricallyopposite longitudinally extending radial lugs adapted to engage in thegrooves in the sleeve and pass longltudinally through the grooves toenter the respective chambers of the sleeve, the portion of the shank ofthe bit below said lugs being circular whereby to engage the circularcentral portion of the bore of the sleeve and rotate therein, the lugsmoving within the recesses of the sleeve during such rotation whereby toaline with and seat in the extensions vat the lower ends of saidrecesses and one wall of a recess being flush with and merging into awall off,"

a seat whereby to limit the rotary movement of thebit and the engagementof the lugs in the seats preventing rotary movement of the bit.

2 The combination of a rotation sleeve provided in its lower end withdiametrically opposite radial longitudinally extending grooves and acentral circular portion connecting the grooves, the sleeve beingfurther provided with shallow recesses, each communicating with theinner end of one of the grooves and extending part way around the innerwall of the sleeve and having a seat in its lower end at the side remotefrom the groove, and a bit provided with a circular shank and withdiametrically opposite lugs at the upper end of the shank, and a bladeextending spirally around the lower portion of the shank, the bladepresenting abrupt shoulders at its upper end wherebythe drill may beinsertedln the grooves and partly rotated to bring the lugs intoenagement with the seats in the sleeve, the width of the shoulders atthe upper ends of the blade being greater than the width of the groovewhereby the shoulders cannot enter the grooves but may abut the lowerend of the sleeve.

In testimony whereof I afix m signature.

WILLIAM STEPHEN [1,. s.]

